Revert "Remove the HTMLVideoElement-specific prefixed fullscreen API"

Source/core/html/HTMLMediaElement.h

Index: Source/core/html/HTMLMediaElement.h
diff --git a/Source/core/html/HTMLMediaElement.h b/Source/core/html/HTMLMediaElement.h
index 5a1ab2d7f1c2e118bde314d677a5b9d70b2b57a7..264e781efe12c98cf3f5067f7768a4c713f9aa9f 100644
--- a/Source/core/html/HTMLMediaElement.h
+++ b/Source/core/html/HTMLMediaElement.h
@@ -235,6 +235,7 @@ public:
 
     bool isFullscreen() const;
     virtual void enterFullscreen() OVERRIDE FINAL;
+    void exitFullscreen();
 
     virtual bool hasClosedCaptions() const OVERRIDE FINAL;
     virtual bool closedCaptionsVisible() const OVERRIDE FINAL;
@@ -285,6 +286,20 @@ protected:
 
     void setControllerInternal(PassRefPtr<MediaController>);
 
+    // Restrictions to change default behaviors.
+    enum BehaviorRestrictionFlags {
+        NoRestrictions = 0,
+        RequireUserGestureForPlayRestriction = 1 << 0,
+        RequireUserGestureForFullscreenRestriction = 1 << 1,
+    };
+    typedef unsigned BehaviorRestrictions;
+
+    bool userGestureRequiredForPlay() const { return m_restrictions & RequireUserGestureForPlayRestriction; }
+    bool userGestureRequiredForFullscreen() const { return m_restrictions & RequireUserGestureForFullscreenRestriction; }
+
+    void addBehaviorRestriction(BehaviorRestrictions restriction) { m_restrictions |= restriction; }
+    void removeBehaviorRestriction(BehaviorRestrictions restriction) { m_restrictions &= ~restriction; }
+
     bool ignoreTrackDisplayUpdateRequests() const { return m_ignoreTrackDisplayUpdate > 0; }
     void beginIgnoringTrackDisplayUpdateRequests();
     void endIgnoringTrackDisplayUpdateRequests();
@@ -406,6 +421,8 @@ private:
 
     void changeNetworkStateFromLoadingToIdle();
 
+    void removeBehaviorsRestrictionsAfterFirstUserGesture();
+
     const AtomicString& mediaGroup() const;
     void setMediaGroup(const AtomicString&);
     void updateMediaController();
@@ -452,6 +469,8 @@ private:
     blink::WebLayer* m_webLayer;
     bool m_opaque;
 
+    BehaviorRestrictions m_restrictions;
+
     MediaPlayer::Preload m_preload;
 
     DisplayMode m_displayMode;
@@ -469,7 +488,6 @@ private:
     PendingActionFlags m_pendingActionFlags;
 
     // FIXME: MediaElement has way too many state bits.
-    bool m_userGestureRequiredForPlay : 1;
     bool m_playing : 1;
     bool m_shouldDelayLoadEvent : 1;
     bool m_haveFiredLoadedData : 1;